TheClimateChanger

Lol - I think I may have triggered CloudFlare due to too many linked images. Regardless, NCEI lists the DJF mean for Michigan's Division 10 [Southeast Lower division] for 1961-1990 as 23.6F, and for 2001-2025 as 26.9F, which is an increase of 3.3F. This is actually slightly more than DTW's increase. I guess NCEI is in on the conspiracy!

Lol, calm down. Here is U of Mich - Ann Arbor coop site. At U of M, the average increased from 25.7F in 1961-1990 to 27.9F in the most recent 25 years (+2.2F). That lends some credence to your theory; however, there is an uncorrected non-climatic bias in this data. The early data is based on an observation time [set max] of 5 pm, versus a standard 24-hour day (see, e.g., below). This results in a warming of about 0.5C/0.9F relative to a midnight to 11:59 p.m. day. Also, here is nearby Toledo, Ohio. The increase is even more substantial than Detroit (+3.8F). Let's play find the Urban Heat Island effect at Toledo Express Airport. It's surrounded by woods and farms, and shows even more warming relative to DTW.

Again, you are reading things that I didn't say. I mean a 1995-1996 or 2009-2010 type year. As @bluewavepointed out, even relative to 2013, the available pool of arctic air is much smaller. If the 2030s are as much above normal as recent decades, PHL could see a decadal winter mean of ~38F. That is on par with the late 20th century average at Richmond, Virginia. Snowfall averaged around 16-17 inches at Richmond in this era, with high snowfall years around 40" or so. This really isn't super different from PHL's average of ~21-22 inches, but I would probably expect mean snowfall to fall more into that range over the next 15 years. And PHL has only seen a few years with substantially more than 40" in the last few decades anyway.

I didn't say that. Especially northern areas are still cold enough to benefit from increased moisture availability, but the baseline climate of more southern Mid Atlantic climates has shifted so much that significant snowfall in even a "normal" temperature regime requires lots of needle threading. Certainly, they could still do well in a particularly cold winter [relative to the norms]. I just wanted to examine what Chuck had posited a few pages back with a possible shift in PDO/AMO. It might be rather surprising but each of the last 4 decades in the east has winded up above normal for temperatures in the wintertime, relative to the existing normals.

Philadelphia 1961-1990 mean: 32.9F Incomplete 2001-2030 mean: 36.7F (+3.8F over 1961-1990) Maybe a place like Detroit is still cold enough for big time snows even in a warmer than normal regime, but it would be hard to envision a scenario where Philadelphia sees hefty snows in the 2030s if the 2030s average say 1.5-2F above the 2001-2030 means, with such a mild baseline climate.

For instance, here is Detroit: 1961-1990 average wintertime mean is 25.4F. Incomplete 2001-2030 average is currently up to 28.6F (+3.2F over 1961-1990)

The 1990s had a ton of high snow years despite being a blow torch overall. By the 2030s, normals will be too high for such a scenario to even be possible. Normals will have have climbed 3-5F over 1961-1990 normals by 2031. A normal winter in the 2030s would have looked like a blow torch in 1999. This is undeniable and factual.

Winters from each decade compared to the then-applicable climate norms. Dating back to at least the 1990s, there has never been a decade in the northeast or midwest that was even close to being below the applicable normal temps for winter temperatures. I would highly doubt that trend changes now. 1991-2000 mean versus 1961-1990 base period: 2001-2010 mean versus 1971-2000 base period: 2011-2020 mean versus 1981-2010 base period: 2020s (to date) mean versus 1991-2020 base period:

True. Although I would argue you could conceive of a scenario where earth approaches snowball conditions, if there were to be a major impact event that blocked out most sunlight for years or decades that was well timed with the peak of a Milankovitch-driven glacial maximum. CO2 levels are typically around 175-180 ppm during glacial maximum. Such an abrupt cooling superimposed upon a landscape already marked by widespread continental-scale glaciers and extremely low levels of GHGs could plausibly lead to such an expansive ice field that it could be difficult to re-emerge into typical Milankovitch-driven interglacial condition, despite the sun's increased solar output. Not sure if such a scenario has ever been modelled.

Apparently, there was indeed a tornado on Friday, but damage was minimal. It appears to have touched down a little before this warning was issued.

I simply said I thought people (generally) were in denial of the recent changes. There is a poster here who loves calling everyone "cyclical climate deniers" and "urban heat island deniers" and "natural climate change deniers" after ironically claiming in 2021 that it was offensive term due to its common use in the context of Holocaust denial: Showing results for 'deniers' in content posted by ChescoWx. - American Weather Showing results for 'denier' in content posted by ChescoWx. - American Weather He especially loves calling people by the pejorative alarmist(s): Showing results for 'alarmists' in content posted by ChescoWx. - American Weather Showing results for 'alarmist' in content posted by ChescoWx. - American Weather Funny, I don't see you calling out this poster.

Did I call anyone names? Can anyone find where I called someone a name in this thread? I was called a "troll" but don't recall calling any one a name.

1947-48 was mostly below normal snowfall in the Lakes. The Northeast and New England fared way better.

The 1940s had some impressive winters. 1944-1945 had very impressive snow cover in the lower Great Lakes region, and 1947-48 was very snowy in the northeast, especially around Worcester. I think they had like 3 feet of snow on the ground in February in Worcester, Massachusetts and that's from when observations were taken in town and not at the more upland airport location. 1948-49 & 1949-50 were low snow, but very cold and snowy in parts of the northern Plains and northwest. I would point out, however, that 1950 was the coldest year overall for the U.S. since 1929, and 1951 was even colder, per NCEI. 1950-51 was very snowy in the Ohio Valley and Appalachians.

Perhaps for the eastern United States, but certainly not globally.

I think people are still in denial mode here. The change from 2011-2013 era to the last 36 months or so has been on the order of .5C. The 1990s are about as cold globally compared to the present, as the 1800s were to the 1990s. It makes little sense to run a linear regression back to the 1800s, when there was a relatively stable climate [only comparatively modest increase] from 1880 to 1970. Not even getting into site changes and changes in protocol. A lot of river cities saw moves to suburban airports with elevation increases of 300 to 500 feet versus downtown. With that said, in many cases, going back further to 1960 or 1970 would, in the majority of cases, increase the decline, by including snowier years from the 1960s to early 1980s. My analysis actually starts with a few notoriously low snow winters, a fact that @LibertyBellsaid was "ironic."

You are incorrect. The last several winters have been well below the trendline, suggesting an accelerating decrease. It would actually take a couple of somewhat above trend years just to keep the trendline at the same slope. If the next few winters were way above normal, then, yes, the trendline would increase. But I don't believe that will happen. Certainly, the occasional year could be way above normal. I mean Charleston, West Virginia had 106" of snow in 1995-96, which is more than 2 feet more than the most observed in Pittsburgh. But the 1961-1990 average at Charleston was ~31" versus ~42" at Pittsburgh.

I didn't say that. I pointed out first order sites have a warm bias from that era, which is well supported by actual research.

I didn't say the atmosphere doesn't hold moisture. Just that there's only a modest positive trend in total precipitation in the winter months. I went back and looked at DJFM and there's actually a decreasing trend further south (DC & Baltimore) over those four months. An increase in moisture tells us little about snowfall, without considering temperature. The atmosphere over Charlotte, North Carolina holds, on average, more moisture in the winter than New York City - but obviously Charlotte doesn't get more snowfall.

It's now "cherrypicking" to end a trend using all available data up through the most recent year rather than cutting off over a decade ago? And you used your backyard when I looked at dozens of sites across the lower Great Lakes, Ohio Valley and East Coast.

No need to call someone a troll for having a different opinion than you.

Snowfall is down across the board since 1989-1990, as shown by linear regression. So I don't think we need to posit some sort of "increase in moisture" was causing increased snowfall. I don't believe there is much evidence to support this hypothesis anyways. Winter precipitation is up less than one inch in most places since the 1800s, so that could only explain at most ~10-12" of additional snow since the 1800s [if temperatures permit], and the difference since the late 19th century is negligible. It was simply a period of natural variability favoring higher snowfall superimposed over a long term downward trend. Here is Boston, just for an example. At BOS, the linear regression goes from 52.5 -> 38.7. NYC has been a little luckier but still downward [maybe not statistically significant though]: 28.9 -> 25.9 PHL: 22.8 -> 19.9 DCA: 14.9 -> 11.2 BWI: 20.9 -> 15.1 A few additional inland sites: MDT: 33.0 -> 22.7 IPT: 42.1 -> 25.7 AVP: 47.4 -> 30.5 Why do we need to blame everything on climate change? The higher snowfall period in the 2000s & 2010s, like the one in the mid 90s, was likely natural variability imposed on a downward trend. Recent years show natural variability acting in the same direction as trend, amplifying low snowfall years.

I didn’t start the discussion. Why don’t you instead call out the person or persons who did?

Recent winters have been rather mild, although the most recent winter was colder. But in +1.5C world, they might actually be fairly ordinary winters. For all we know, last winter is as good as it gets in a +1.5C world. A warm winter in that world might bring even milder conditions. We just don't have enough data to say what a typical winter looks like in a +1.5C world, since we've only been at those levels for a couple of years. I mean the last glacial maximum was only ~6C colder, and that had mountains of ice burying many of these cities. Summer temperatures would have been hardpressed to get much above freezing for any extended periods of time, and snowfall would have been probable in every month of the calendar year. These days summers are warm and humid, with highs regularly in the 80s, and occasionally in the 90s. So, I don't think it should be controversial to say an increase of about 1/4 of the difference between pre-industrial average and glacial maximum is capable of causing a decrease in winter snowfall?

Is there a mechanism by which snowfall can increase? I just don't understand what magical change is going to take place that we "cycle" into a snowier period. Makes zero sense in a rapidly warming world. Laughably stupid. Sure, there can still be snowier and colder winters from time to time, but I just don't see the current trend reversing? But maybe I am missing something?